JP7735675B2 - Control device, control system, control method and program - Google Patents

Description

The present invention relates to a control device, a control system, a control method, and a program.

When a robot and a worker work together, a virtual protection area is set near the robot, and sensors are used to monitor whether the worker has entered the protection area. The protection area is set with a safe distance in mind relative to the robot's range of motion. If a worker enters the protection area, the robot's movements are slowed down or stopped, ensuring the worker's safety. Patent Document 1 discloses that the robot's movements are slowed down or stopped when it is determined that the person's position is within a specified range.

Japanese Patent Application Laid-Open No. 2014-8562

Conventionally, when a robot is close to a person, the robot's movement is slowed down or stopped, but if the robot's movement has to be slowed down or stopped frequently, the robot's operating efficiency decreases.

The present invention was made in consideration of the above-mentioned circumstances, and its purpose is to provide technology that can prevent a decline in the operating efficiency of a robot.

A control device according to one aspect of the present invention includes a control unit that controls the operation of a robot; an acquisition unit that acquires the frequency with which a worker is present at a position based on statistical information about the worker's position within a monitoring area; and a modification unit that modifies the path information based on information about locations where the frequency with which the worker is present is higher than a threshold and path information that includes at least the start and end points of the robot's operation, and the control unit controls the operation of the robot based on the modified path information.

With the above configuration, route information is changed based on information about locations where workers are present more frequently than a threshold value and route information that includes at least the start and end points of the robot's movement, and the robot's movement is controlled based on the changed route information. This allows the robot's movement to be controlled based on route information that has been changed in response to information about locations where workers are present more frequently than a threshold value. By controlling the robot's movement based on the changed route information, the frequency with which the robot's movement slows down or stops can be reduced compared to when the robot's movement is controlled based on the route information before the change. This prevents a decrease in the robot's movement efficiency.

The change unit may create one or more waypoints for the robot to pass through based on information about locations where the worker is present more frequently than a threshold and the route information, and the changed route information may include one or more of the waypoints. By controlling the robot's operation based on one or more waypoints included in the changed route information, it is possible to prevent a decrease in the robot's operating efficiency.

The change unit may create a plurality of waypoints for the robot to pass through based on information about the plurality of places where the worker is present more frequently than a threshold value and the route information, and the changed route information may include the plurality of waypoints. With this configuration, the route information can be changed in accordance with the plurality of places where the worker is present more frequently than a threshold value.

If the distance between two of the multiple waypoints is less than a certain distance, the change unit may remove one of the two waypoints that is closer to the location where the frequency of the worker's presence is higher than a threshold. This configuration increases the distance between two consecutive waypoints, suppressing unnecessary robot movements and reducing the robot's operating efficiency.

One or more of the waypoints may be a predetermined distance or more away from a location where the frequency of the worker's presence is higher than a threshold. Since one or more waypoints included in the changed route information are a predetermined distance or more away from a location where the frequency of the worker's presence is higher than a threshold, controlling the robot's operation based on the changed route information can prevent a decrease in the robot's operating efficiency.

The change unit may create a path for the robot to travel based on information about locations where the worker is present more frequently than a threshold and the route information, and the changed route information may include the path. By controlling the robot's operation based on the path included in the changed route information, it is possible to prevent a decrease in the robot's operation efficiency. The path may be located a predetermined distance or more away from locations where the worker is present more frequently than a threshold. Because the path included in the changed route information is located a predetermined distance or more away from locations where the worker is present more frequently than a threshold, it is possible to prevent a decrease in the robot's operation efficiency by controlling the robot's operation based on the changed route information.

When there are multiple locations where the worker is present more frequently than a threshold, the route information before the change includes a first path traversed by the robot, and all of the following conditions are met: (1) the distance between the start point and a first location, which is one of the multiple locations where the worker is present more frequently than a threshold, is equal to or greater than a predetermined distance; (2) the distance between the first location and the end point is equal to or greater than the predetermined distance; and (3) the distance between the first location and the first path is equal to or greater than the predetermined distance, the change unit does not change the route information based on the information about the first location. When there are multiple locations where the worker is present more frequently than a threshold, and the distance between the start point or the end point, which is one of the multiple locations where the worker is present more frequently than a threshold, is shorter than a predetermined distance, the change unit does not change the route information based on the information about the second location.

The acquisition unit may acquire the frequency at which the worker corresponding to the worker information is present based on the statistical information and the worker information of the worker, and the change unit may change the route information based on information about locations where the frequency at which the worker corresponding to the worker information is present is higher than a threshold and the route information. With this configuration, the route information can be changed in accordance with the worker information of the worker, preventing a decrease in the robot's operating efficiency.

The acquisition unit may acquire the frequency of presence of the worker corresponding to the work process information based on the statistical information and the work process information of the robot, and the change unit may change the route information based on information about locations where the frequency of presence of the worker corresponding to the work process information is higher than a threshold value and the route information. With this configuration, the route information can be changed in accordance with the work process information of the robot, preventing a decrease in the robot's operating efficiency.

The acquisition unit may acquire the frequency of presence of the worker corresponding to the surrounding information based on the statistical information and the surrounding information of the worker, and the change unit may change the route information based on information about locations where the frequency of presence of the worker corresponding to the surrounding information is higher than a threshold value and the route information. With this configuration, the route information can be changed in accordance with the surrounding information of the worker, preventing a decrease in the operating efficiency of the robot.

The acquisition unit may acquire the frequency of presence of the worker corresponding to the statistical information and at least two pieces of information from among worker information about the worker, work process information about the robot, and information about the worker's surroundings, and the change unit may change the route information based on information about locations where the frequency of presence of the worker corresponding to the two pieces of information is higher than a threshold and the route information.

A control device according to one aspect of the present invention may include a setting unit that sets a protection area within the monitoring area to detect intrusion of the worker based on the changed path information. Setting the protection area based on the changed path information reduces the possibility of a worker intruding into the protection area, preventing a decrease in the robot's operating efficiency.

The present invention can also be understood as a control system that performs at least part of the above-mentioned processing, a control method that includes at least part of the above-mentioned processing, or a program for implementing such a method or a recording medium on which such a program is non-temporarily recorded. Furthermore, the above-mentioned means and processing can be combined with each other to the greatest extent possible to constitute the present invention.

The present invention provides technology that can prevent a decline in robot operating efficiency.

FIG. 1 is a schematic diagram of a control system according to this embodiment. FIG. 2 is a block diagram of the control device according to this embodiment. FIG. 3 is a plan view of the robot according to this embodiment. FIG. 4 is a plan view of the robot according to this embodiment. FIG. 5 is a plan view of the robot according to this embodiment. FIG. 6 is a plan view of the robot according to this embodiment. FIG. 7 is a hardware configuration diagram of the control device according to this embodiment. FIG. 8 is a flowchart illustrating the processing flow of the control system according to this embodiment. FIG. 9 is an explanatory diagram of the safe distance. FIG. 10 is a plan view of the robot according to this embodiment. FIG. 11 is a plan view of the robot according to this embodiment. FIG. 12 is a plan view of the robot according to this embodiment. FIG. 13 is a plan view of the robot according to this embodiment. FIG. 14 is a plan view of the robot according to this embodiment. FIG. 15 is a plan view of the robot according to this embodiment. FIG. 16 is a plan view of the robot according to this embodiment.

<Application example>
FIG. 1 is a schematic diagram of a control system according to this embodiment. The control system of FIG. 1 grasps the movements of a worker 10 and controls the robot 1 in an environment where the robot 1 and a human worker 10 coexist, for example, in a production site such as a factory. The robot 1 of FIG. 1 is a vertical articulated robot and includes a base 11 and an arm 12 connected to the base 11. The robot 1 is not limited to a vertical articulated robot and may be a robot employing other methods, such as a horizontal articulated robot. An end effector (hand) for grasping an object is attached to the tip of the arm 12. The robot 1 further includes a servo motor for operating the arm 12. In FIG. 1, the robot 1 is placed on a workbench 2.

The control system includes a robot 1, a control device 3 that controls the robot 1, and a sensor 4 that serves as a detection unit that detects the positions of the robot 1 and the worker 10. The sensor 4 detects the positions of the robot 1 and the worker 10 at regular or irregular intervals and sends the position information of the robot 1 and the worker 10 to the control device 3. The sensor 4 may also continuously detect the positions of the robot 1 and the worker 10 and send the position information of the robot 1 and the worker 10 to the control device 3.

Sensor 4 is a distance measurement sensor that measures the distance to an object. Sensor 4 may be RADAR (Radio Detection and Ranging), LiDAR (Light Detection and Ranging), or a 3D camera. Sensor 4 may also be a sensor system that combines at least two of RADAR, LiDAR, and a 3D camera. The position of robot 1 may be a relative position within the measurable area (detection range) of sensor 4. The measurable area of sensor 4 is also called the monitored area (monitored area). The position of robot 1 may be the position of each part of robot 1. For example, the position of robot 1 may be the position of the tip of arm 12, the position of an end effector attached to the tip of arm 12, or the position of base 11. The position of worker 10 may be a relative position within the measurable area of sensor 4. The position of worker 10 may be the position of each part of worker 10. For example, the position of worker 10 may be the position of the worker's hands, feet, or head.

As shown in FIG. 1, a protection area 20 is set between the robot 1 and the worker 10. The protection area 20 is a virtual three-dimensional area for detecting intrusion of the worker 10, and is set near or around a hazard source such as the robot 1. Multiple protection areas 20 can be set. The protection area 20 is determined in accordance with safety standards and taking into account the operating range of the robot 1. For example, if an object such as the worker 10 intrudes into the protection area 20, safety control such as slowing down or stopping the operation of the robot 1 is performed. The sensor 4 is positioned and the field of view of the sensor 4 is set so that the protection area 20 is included within the measurable area of the sensor 4.

Figure 2 is a block diagram of the control device 3. The control device 3 includes a robot controller 31 that controls the operation of the robot 1, a creation unit 32 that creates path information, an acquisition unit 33 that acquires the frequency with which the worker 10 is present within a predetermined area, a modification unit 34 that changes the path information, a setting unit 35 that sets the protection area 20, and a memory unit 36. The path information includes at least the start and end points of the robot 1's operation. In addition to the start and end points of the robot 1's operation, the path information may also include information such as the path from the start to the end point of the robot 1's operation.

The robot controller 31 controls the operation of the robot 1 based on the path information. The robot controller 31 is an example of a control unit. The robot controller 31 also controls the start, stop, deceleration, and acceleration of the operation of the robot 1. FIG. 3 is a plan view of the robot 1. FIG. 3 shows the state in which the tip of the arm 12 of the robot 1 moves from a start point SP to an end point EP. The arm 12 before the movement is shown by a solid line, and the arm 12 after the movement is shown by a dotted line. Here, a path P1 from the start point SP to the end point EP is set as a straight line. By setting the path P1 as a straight line, the movement distance of the arm 12 of the robot 1 is minimized, and the operation efficiency of the robot 1 is high. A protection area 20 is set near the path P1. Obstacles 5, such as pillars, are placed on both sides of the robot 1. Because the worker 10 cannot enter an area where the obstacles 5 are placed, the protection area 20 is not set in the area where the obstacles 5 are placed.

Each time the position of the worker 10 is detected by the sensor 4, the robot controller 31 determines whether the worker 10 has entered the protection area 20. If the worker 10 has entered the protection area 20, the robot controller 31 slows down or stops the operation of the robot 1. Alternatively, a safety determination unit separate from the robot controller 31 may determine whether the worker 10 has entered the protection area 20 and transmit the determination result to the robot controller 31. The distance S1 in the planar direction of the protection area 20 may be a safety distance defined by a safety standard. The creation unit 32 creates path information according to the work (process) of the robot 1 and stores the path information in the memory unit 36. The creation unit 32 may also acquire path information from an external device connected to the control device 3 and store the path information in the memory unit 36.

The acquisition unit 33 acquires the frequency with which the worker 10 is present at the position of the worker 10 within a predetermined area based on statistical information on the position of the worker 10 detected by the sensor 4. The predetermined area may be a monitoring area. The acquisition unit 33 may store the position of the worker 10 detected by the sensor 4 in the memory unit 36 to create statistical information on the position of the worker 10. The predetermined area may be the same size as the measurable area of the sensor 4, or may be smaller than the measurable area of the sensor 4. The predetermined area may include the protection area 20, or a portion of the predetermined area may overlap with a portion of the protection area 20. The frequency with which the worker 10 is present within the predetermined area may be the number of times the position of the worker 10 is detected by the sensor 4. The frequency with which the worker 10 is present within the predetermined area may also be the number of hours the position of the worker 10 is detected by the sensor 4. While the above example illustrates the use of statistical information on the position of the worker 10 detected by the sensor 4, this example is not limiting and statistical information on the position of the worker 10 detected by an imaging device such as a fisheye camera may also be used.

Figure 4 is a plan view of the robot 1. Figure 4 shows locations L1 to L3 within the predetermined area 40 where the frequency of worker 10 presence is higher than a threshold. For example, as shown in Figure 4, a two-dimensional coordinate system parallel to the floor surface may be set, and the predetermined area 40 may be divided into regular intervals, and the number of times the position of the worker 10 is detected may be tallied for each grid. The obtained frequency of worker 10 presence may be used as the frequency of worker 10 presence at each location within the predetermined area 40. Locations L1 to L3 may be circular or rectangular in plan view. The acquisition unit 33 may select locations showing a presence frequency higher than the threshold from a heat map of the worker 10 presence frequency. This allows the acquisition unit 33 to obtain locations within the predetermined area 40 where the frequency of worker 10 presence is higher than the threshold. In addition to the heat map of the worker 10 presence frequency, the acquisition unit 33 may also obtain locations within the predetermined area 40 where the frequency of worker 10 presence is higher than the threshold through machine learning using AI (artificial intelligence) technology such as a convolutional neural network (CNN). In Figure 4, locations where the frequency of presence of workers 10 is higher than a threshold are shown for each grid obtained by dividing the predetermined area 40 at regular intervals, but this is not limited to the example shown in Figure 4. The range of the predetermined area 40 and the range of the measurable area of the sensor 4 may be the same or different. For example, when statistical information on the position of the worker 10 detected by the sensor 4 is used, the range of the predetermined area 40 and the range of the measurable area of the sensor 4 will be the same.

The change unit 34 changes the route information based on information about locations within a predetermined area where the frequency of the presence of the worker 10 is higher than a threshold (hereinafter referred to as "high-frequency locations") and the route information. The change unit 34 may change the route information by creating one or more waypoints for the robot 1 to pass through based on the information about the high-frequency locations and the route information and adding the created one or more waypoints to the route information. In this case, the changed route information may include at least the start and end points of the robot 1's movements and the one or more waypoints. The change unit 34 may also change the route information by creating a new path for the robot 1 to pass through based on the information about the high-frequency locations and the route information and changing the path included in the route information to the newly created path. In this case, the changed route information may include at least the start and end points of the robot 1's movements and the path for the robot 1 to pass through. Furthermore, the change unit 34 may change the route information by adding waypoints to the route information and changing the path included in the route information to the newly created path. In this case, the changed route information includes at least the start and end points of the robot 1's movement, one or more waypoints, and the path that the robot 1 will take.

The setting unit 35 sets at least one protection area 20 in spatial coordinates within the field of view of the sensor 4 to ensure safe work by the robot 1 and worker 10. The protection area 20 indicates a range of three-dimensional coordinates (x coordinate, y coordinate, z coordinate).

Figure 5 is a plan view of the robot 1. Figure 5 shows the start point SP, end point EP, and path P1 connecting the start point SP and end point EP, which are included in the route information. Figure 5 also shows via points VP1 to VP5 created by the modification unit 34, and a newly created path P2. Path P2 is a line connecting the start point SP, via points VP1 to VP5, and end point EP. The line between the start point SP and via point VP1, the lines between via points VP1 to VP5, and the line between via point VP5 and end point EP may be straight or curved. The modification unit 34 may create via points VP1 to VP5 based on information about the high-frequency location L2 and the path P1 in the route information, and modify the route information by adding via points VP1 to VP5 to the route information. The change unit 34 may change the route information by creating a new path P2 for the robot 1 to travel based on the information about the high-frequency location L2 and the path P1 in the route information, and changing the path P1 included in the route information to the path P2.

Via points VP1 to VP5 and path P2 are provided along circle C2, outside circle C2, with a radius a predetermined distance from the center of high frequency location L2. Via points VP1 to VP5 and path P2 may be provided near circle C2. Because via points VP1 to VP5 and path P2 are provided outside circle C2, they are at least a predetermined distance away from high frequency location L2. The angle formed by the imaginary line from the center of high frequency location L2 to via point VP1 and the imaginary line from the center of high frequency location L2 to via point VP2 is arbitrary. The intervals between via points VP1 to VP5 may be the same or different. After creating via points VP1 to VP5 outside circle C2, the modification unit 34 may create path P2 connecting start point SP, via points VP1 to VP5, and end point EP. The modification unit 34 may create a path P2 connecting the start point SP and the end point EP outside the circle C2, and then create via points VP1 to VP5 on the path P2.

The robot controller 31 controls the operation of the robot 1 based on the changed path information. The changed path information includes waypoints VP1 to VP5 or path P2. The changed path information may also include waypoints VP1 to VP5 and path P2. The robot 1 passing through waypoints VP1 to VP5 included in the changed path information moves to a position at least a predetermined distance away from the center of the high frequency location L2. As shown in FIG. 6, the setting unit 35 resets the protection area 20 near path P2, and the robot controller 31 determines whether the worker 10 has entered the protection area 20 each time the sensor 4 detects the worker 10's position.

As shown in Fig. 4, the protection area 20 set near the path P1 overlaps with the high frequency location L2. Therefore, if the operation of the robot 1 is controlled based on the path information before the change, there is a high possibility that the worker 10 will enter the protection area 20, and the operation of the robot 1 will likely be slowed down or stopped frequently. On the other hand, as shown in Fig. 6, the protection area 20 set near the path P2 does not overlap with the high frequency location L2. Therefore, there is a lower possibility that the worker 10 will enter the protection area 20 than if the protection area 20 were set near the path P1. In other words, if the operation of the robot 1 is controlled based on the path information after the change, there is a high possibility that the worker 10 will enter the protection area 20.
The possibility of robot 1 entering the protection area 20 is reduced. Therefore, when the operation of the robot 1 is controlled based on the changed route information, the frequency of the robot 1 slowing down or stopping is reduced. Furthermore, because the waypoints and paths included in the changed route information are located at a predetermined distance or more from high-frequency locations, the frequency of the robot 1 slowing down or stopping is reduced when the operation of the robot 1 is controlled based on the changed route information. In this way, by controlling the operation of the robot 1 based on the changed route information, the frequency of the robot 1 slowing down or stopping can be reduced compared to when the operation of the robot 1 is controlled based on the route information before the change. This prevents a decrease in the operational efficiency of the robot 1, improving productivity.

The above application examples are provided to aid in understanding the present invention and are not intended to limit the scope of the present invention.

<System Configuration>
7 is a hardware configuration diagram of the control device 3. The control device 3 includes a CPU 301, a ROM 302, a RAM 303, a sensor IF 304, a display unit 305, an operation IF 306, and a communication IF 307. The ROM 302 stores a control program executed by the CPU 301. The ROM 302 also stores values such as various thresholds. The RAM 303 provides a work area when the CPU 301 executes the control program.

The sensor IF 304 processes the position information of the robot 1 and the worker 10 sent from the sensor 4 and transmits it to the CPU 301. The display unit 305 is composed of an LCD or the like and displays various information. The operation IF 306 accepts various instructions input from the worker 10 and sends the input information to the CPU 301. The operation IF 306 may also have a function to notify the worker 10 by voice, lamp, etc. based on instructions from the CPU 301. The communication IF 307 performs wired or wireless communication between the CPU 301 and external devices.

As shown in FIG. 2, the control device 3 includes a robot controller 31, a creation unit 32, an acquisition unit 33, a change unit 34, a setting unit 35, and a storage unit 36. The functions of each of these units are realized in software by programs stored in ROM 302. In other words, the CPU 301 loads and executes the necessary programs in RAM 303, and performs various calculations and controls each hardware resource, thereby providing the functions of each unit.

The flow of the route information change process will be explained using the flowchart in Figure 8. The change unit 34 determines whether the distance between the high-frequency location and the start point and end point of the robot 1's movement is equal to or greater than a predetermined distance (step S101). If the distance between the high-frequency location and the start point or end point of the robot 1's movement is shorter than the predetermined distance, the change unit 34 does not change the route information. The start point and end point of the robot 1's movement cannot be changed, and the distance between the high-frequency location and the start point or end point of the robot 1's movement cannot be set to equal to or greater than the predetermined distance. Therefore, the change unit 34 determines that the route information cannot be changed (step S102).

If the distances between the high frequency location and the start point and end point of the robot 1's movement are equal to or greater than the predetermined distance (step S101: YES), the process proceeds to step S103. In step S101, the change unit 34 may create a circle with a radius equal to the predetermined distance from the center of the high frequency location and determine whether the start point and end point of the robot 1's movement are included within the circle. As shown in FIG. 5 , the start point SP and end point EP are not included within the circle C1 in the high frequency location L1 or the circle C2 in the high frequency location L2. In this case, the change unit 34 determines that the distances between the high frequency location L1 and the start point SP and end point EP are equal to or greater than the predetermined distance. Furthermore, the change unit 34 determines that the distances between the high frequency location L2 and the start point SP and end point EP are equal to or greater than the predetermined distance. As shown in FIG. 5 , the end point EP is included within the circle C3 in the high frequency location L3. In this case, the change unit 34 determines that the distance between the high frequency location L3 and the end point EP is shorter than the predetermined distance.

The change unit 34 determines whether the distance between the high-frequency location and the path in the route information is equal to or greater than a predetermined distance (step S103). If the distance between the high-frequency location and the path in the route information is equal to or greater than the predetermined distance (step S103: YES), the change unit 34 does not change the route information. In step S103, the change unit 34 may create a circle with a radius of a predetermined distance from the center of the high-frequency location and determine whether the circle intersects with the path in the route information. As shown in FIG. 5, circle C1 and path P1 at high-frequency location L1 do not intersect. In this case, the change unit 34 determines that the distance between high-frequency location L1 and path P1 is equal to or greater than the predetermined distance. As shown in FIG. 5, circle C2 and path P1 at high-frequency location L2 intersect. In this case, the change unit 34 determines that the distance between high-frequency location L2 and path P1 is shorter than the predetermined distance.

If the distance between the high-frequency location and the path in the route information is shorter than a predetermined distance (step S103: NO), proceed to step S104. In step S104, the change unit 34 creates a new path and via point so that the new path and via point are at least a predetermined distance away from the high-frequency location. The change unit 34 then changes the route information using at least one of the new path and via point. If the distance between the high-frequency location and the path in the route information is equal to or greater than a predetermined distance (step S103: YES), the change unit 34 does not change the route information (step S105).

The change unit 34 determines whether processing has been performed for all high-frequency locations (step S106). If processing has been performed for all high-frequency locations (step S106: YES), the flowchart in FIG. 8 ends. If any high-frequency locations have not been processed (step S106: NO), the process returns to step S101.

5, the start point SP and the end point EP are not included in the circle C1 in the high-frequency location L1, and the circle C1 in the high-frequency location L1 does not intersect with the path P1. Therefore, the change unit 34 does not change the route information based on the information about the high-frequency location L1. In other words, when all of the following conditions (1) to (3) are satisfied, the change unit 44 does not change the route information based on the information about the high-frequency location L1, which is one of the multiple high-frequency locations.
(1) The distance between the high frequency location L1 and the starting point SP is equal to or greater than a predetermined distance.
(2) The distance between the high frequency location L1 and the end point EP is equal to or greater than a predetermined distance.
(3) The distance between the high frequency location L1 and the path P1 is equal to or greater than a predetermined distance.
The information on the high-frequency location L1 is an example of information on a first location. The path P1 is an example of a first path. As shown in FIG. 5 , the circle C2 in the high-frequency location L2 does not include the start point SP or the end point EP, and the circle C2 in the high-frequency location L2 intersects with the path P1. Therefore, the change unit 34 changes the route information based on the information on the high-frequency location L2.

As shown in FIG. 5 , the end point EP is included within the circle C3 in the high-frequency location L3. Therefore, the change unit 34 does not change the route information based on the information about the high-frequency location L3. That is, if the distance between the high-frequency location L3, which is one of the multiple high-frequency locations, and the start point SP or the end point EP is shorter than a predetermined distance, the change unit 34 does not change the route information based on the information about the high-frequency location L3. The information about the high-frequency location L3 is an example of second location information. In this case, the change unit 34 may notify the worker 10 of this information by displaying the high-frequency location L3 and information indicating that the route information was not changed on the display unit 305. For example, in a work process in which the worker 10 picks up a workpiece carried by the robot 1, the robot 1 and the worker 10 may come close to each other. By notifying the worker 10 of the high-frequency location L3 and information indicating that the route information was not changed, it is possible to encourage the worker 10 to improve the work process.

The acquisition unit 33 may acquire the frequency with which a worker 10 corresponding to the worker information is present within a predetermined area based on statistical information on the location of the worker 10 detected by the sensor 4 and information about the worker 10 (hereinafter referred to as "worker information"). The worker information may include the name and ID number of the worker 10. For example, the frequency with which a skilled worker 10 is present within a predetermined area may differ from that of a non-skilled worker 10. The acquisition unit 33 may associate the location of the worker 10 detected by the sensor 4 with the worker information, store the location of the worker 10 and the worker information in the memory unit 36, and create statistical information on the location of the worker 10 corresponding to the worker information. For example, the worker 10 may wear an information storage unit such as an RFID tag that stores the worker information. In this case, a reading unit such as a reader/writer reads the worker information from the RFID tag, and the acquisition unit 33 acquires the worker information from the reader/writer. Furthermore, for example, the operation IF 306 may accept input of worker information from the worker 10, and the acquisition unit 33 may acquire the input worker information. The change unit 34 may change the route information based on information about locations within a predetermined area where the frequency of presence of the worker 10 corresponding to the worker information is higher than a threshold value, and the route information. This makes it possible to change the route information in accordance with the worker information, further preventing a decrease in the operating efficiency of the robot 1.

The acquisition unit 33 may acquire the frequency with which the worker 10 corresponding to the work process information is present within a predetermined area based on statistical information on the position of the worker 10 detected by the sensor 4 and information on the work process of the robot 1 (hereinafter referred to as "work process information"). For example, if work process A of the robot 1 is different from work process B of the robot 1, the frequency with which the worker 10 is present within the predetermined area will differ. The acquisition unit 33 may associate the position of the worker 10 detected by the sensor 4 with the work process information, store the position of the worker 10 and the work process information in the memory unit 36, and create statistical information on the position of the worker 10 corresponding to the work process information. For example, the operation IF 306 may accept input of the work process information from the worker 10, and the acquisition unit 33 may acquire the input work process information. The modification unit 34 may modify the route information based on information on locations within the predetermined area where the frequency with which the worker 10 corresponding to the work process information is present is higher than a threshold, and the route information. This allows the path information to be changed according to the work process information, further preventing a decline in the operational efficiency of the robot 1.

The acquisition unit 33 may acquire the frequency of presence of the worker 10 corresponding to the worker peripheral information within a predetermined area based on statistical information on the position of the worker 10 detected by the sensor 4 and information on the worker's 10's surrounding conditions (hereinafter referred to as "worker peripheral information"). For example, the worker peripheral information is position information of a mobile robot. When a mobile robot moves around the worker 10, the frequency of presence of the worker 10 within the predetermined area varies. The acquisition unit 33 may associate the position of the worker 10 detected by the sensor 4 with the worker peripheral information, store the position of the worker 10 and the worker peripheral information in the memory unit 36, and create statistical information on the position of the worker 10 corresponding to the worker peripheral information. The sensor 4 may detect the position of the mobile robot, and the acquisition unit 33 may acquire the mobile robot's position information from the sensor 4. The change unit 34 may change the route information based on information on locations within the predetermined area where the frequency of presence of the worker 10 corresponding to the worker peripheral information is higher than a threshold, and the route information. This allows the route information to be changed according to the information about the worker's surroundings, further preventing a decrease in the robot 1's operating efficiency.

The acquisition unit 33 may acquire, based on statistical information on the positions of the workers 10 detected by the sensor 4 and at least two pieces of information from among the worker information, work process information, and worker surroundings information, the frequency with which the workers 10 corresponding to these two pieces of information are present within a specified area. The modification unit 34 may modify the route information based on information on locations where the frequency with which the workers 10 corresponding to at least two pieces of information from the worker information, work process information, and worker surroundings information are present within a specified area is higher than a threshold value, and the route information.

The predetermined distance described in the flowchart of FIG. 8 may be a safety distance. The safety distance will be described with reference to FIG. 9. In 5.5.4.2.3 of ISO/TC15066, the safety distance Sp is defined as "Sp(t0) = Sh + Sr + Ss + c + Zd + Zr". In the above definition formula, "Sh" indicates "the distance a person travels from the current time until the robot stops moving", and "Sr" indicates "the distance a robot travels from the current time until the robot starts its stopping operation". "Ss" in the above definition formula indicates "the distance a robot travels from the time the robot starts its stopping operation until the robot stops moving". "c" in the above definition formula stands for "Depth Penetration
It is called a "factor" and indicates, for example, the distance from a detection position such as the center (center of gravity) of a person to a part of the person such as an arm. In the above definition, "Zd" indicates the measurement error of the sensor that detects the human body, and "Zr" indicates the error of the control position in robot control.

With reference to Figures 10 to 15, the process of changing route information based on multiple high-frequency locations will be described. Figures 10 to 15 are plan views of the robot 1. As shown in Figure 10, high-frequency location L4 and high-frequency location L5 overlap. In Figures 10 to 15, the protection area 20 and predetermined area 40 are not shown. First, as shown in Figure 11, the change unit 34 creates a circle C4 with a radius a predetermined distance from the center of the high-frequency location L4, and creates waypoints VP1 to VP6 for the high-frequency location L4.

As shown in FIG. 12, the modification unit 34 creates a circle C5 with a radius a predetermined distance from the center of the high-frequency location L5, and creates via points VP7 to VP12 for the high-frequency location L5. If a via point set for another high-frequency location is located within a predetermined distance from the center of the target high-frequency location, the modification unit 34 removes the via point located within a predetermined distance from the center of the target high-frequency location. In FIG. 13, the modification unit 34 removes via point VP7 located within a predetermined distance from the center of the high-frequency location L4, and via points VP5 and VP6 located within a predetermined distance from the high-frequency location L5. In FIG. 13, the removed via points VP5, VP6, and VP7 are displayed as black circles.

When multiple via points are located within a certain distance (in Figure 14, the radius of circle C6 located outside via point VP3), the modification unit 34 retains via points farther from the high-frequency location and removes via points closer to the high-frequency location. In Figure 14, via points VP3 and VP8 are located within the certain distance, and the distance from via point VP3 to high-frequency location L5 is longer than the distance from via point VP8 to high-frequency location L4. Of via points VP3 and VP8 located within the certain distance, the modification unit 34 retains via point VP3 and removes via point VP8. Similarly, of via points VP4 and VP9 located within the certain distance, the modification unit 34 retains via point VP9 and removes via point VP4. The certain distance may be set, for example, as the spacing between multiple via points. The spacing between multiple via points may be calculated using a predetermined distance (e.g., a safety distance) when setting multiple via points and a set angle for the via points (e.g., a central angle of 10 degrees). As shown in FIG. 15, the modification unit 34 modifies the route information by creating a new path P3 that passes through the remaining way points V1 to V3 and V9 to V12. In this way, if the distance between two of the multiple way points is less than a certain distance, the modification unit 34 removes one of the two way points that is the shorter distance from the high-frequency location. This increases the distance between two consecutive way points, making it possible to suppress unnecessary movements of the robot 1 and prevent a decrease in the robot's operating efficiency.

When the path information is changed, the robot controller 31 may refer to the information stored in the storage unit 36 to determine whether the robot 1 is capable of operating based on the changed path information. A case where the robot controller 31 determines that the robot 1 is unable to operate based on the changed path information will be described. A first method of dealing with the situation when it is determined that the robot 1 is unable to operate will be described. As the first method of dealing with the situation, the change unit 34 may not change the path information. While the frequency of deceleration and stopping of the robot 1's operation remains unchanged, it is possible to prevent the setting of path information that does not allow the robot 1 to operate.

As a second countermeasure, as shown in FIG. 16, the modification unit 34 may shorten the radius (predetermined distance) of the circle C2 in the high-frequency location L2 and reset the waypoints VP1 to VP6. The protection area 20 and the predetermined area 40 are not shown in FIG. 16. As shown in FIG. 16, compared to before the radius of the circle C2 was shortened, the modified path P2 is set closer to the high-frequency location L2. As a result, it is no longer possible to completely avoid contact or collision between the robot 1 and the worker 10. However, compared to before the radius of the circle C2 was shortened, it is possible to reduce the frequency with which the robot 1 slows down or stops when the worker 10 enters the protection area 20.

The processes described above may be considered to be methods executed by a computer. Furthermore, a program for causing a computer to execute the processes described above may be provided to the computer via a network or from a computer-readable recording medium that non-temporarily stores data. By loading and executing the program into a computer, the computer can function as the control device 3. The processes described above may be performed by loading and executing the program into a computer, the computer can function as the control device 3.

<Additional Notes>
A control unit (31) for controlling the operation of the robot (1);
an acquisition unit (32) that acquires the frequency with which the worker (10) is present within a predetermined area based on statistical information on the position of the worker (10) detected by the detection unit (4);
a change unit (33) that changes the path information based on information about a location where the frequency of the presence of the worker (10) is higher than a threshold value and path information including at least a start point and an end point of the movement of the robot (1);
Equipped with
The control unit (31) controls the operation of the robot based on the changed path information.

1: Robot 2: Workbench 3: Control device 4: Sensor 10: Worker 20; Protected area 31: Robot controller 32: Creation unit 33: Acquisition unit 34: Change unit 35: Setting unit 36: Storage unit

Claims (16)

a control unit that controls the operation of the robot;
an acquisition unit that acquires a frequency at which the worker is present at a position based on statistical information on the position of the worker within a monitoring area;
a change unit that changes the path information based on information about a location where the frequency of the worker's presence is higher than a threshold value and path information that includes at least a start point and an end point of a movement of the robot ;
Equipped with
the control unit controls the operation of the robot based on the changed path information;
There are a plurality of locations where the frequency of the presence of the worker is higher than a threshold value,
When a distance between a second location, which is one of a plurality of locations where the frequency of the worker being present is higher than a threshold, and the start point or the end point is shorter than a predetermined distance, the change unit does not change the route information based on information about the second location.
Control device. the change unit creates one or more waypoints for the robot to pass through based on information about locations where the frequency of the worker's presence is higher than a threshold and the route information;
The control device according to claim 1 , wherein the changed route information includes one or more of the waypoints. the change unit creates a plurality of waypoints through which the robot passes, based on information on a plurality of locations where the frequency of the worker's presence is higher than a threshold and the route information;
The control device according to claim 1 , wherein the changed route information includes a plurality of the via points. The control device according to claim 3 , wherein, when the distance between two of the plurality of the waypoints is equal to or less than a certain distance, the change unit removes one of the two waypoints that is closer to the location where the frequency of the worker's presence is higher than a threshold value. The control device according to claim 2 , wherein one or more of the waypoints are located at least the predetermined distance away from a location where the frequency of the presence of the worker is higher than a threshold value. the change unit creates a path for the robot to take based on information about locations where the frequency of the worker's presence is higher than a threshold and the route information;
The control device according to claim 1 , wherein the route information after the change includes the path. The control device according to claim 6 , wherein the path is located at least the predetermined distance from a location where the frequency of the worker's presence is higher than a threshold value. the route information before the change includes a first path along which the robot passes,
The change unit
(1) The distance between the start point and a first location, which is one of a plurality of locations where the frequency of the presence of the worker is higher than a threshold, is equal to or greater than the predetermined distance.
(2) The distance between the first location and the end point is equal to or greater than the predetermined distance.
(3) the distance between the first location and the first path is equal to or greater than the predetermined distance;
The control device according to claim 1 , wherein when all of the above conditions are met, the route information based on the information about the first location is not changed. the acquiring unit acquires a frequency of presence of the worker corresponding to the worker information based on the statistical information and the worker information of the worker;
The control device according to claim 1 , wherein the change unit changes the route information based on information about a location where the frequency of presence of the worker corresponding to the worker information is higher than a threshold value and the route information. the acquisition unit acquires a frequency of presence of the worker corresponding to the work process information based on the statistical information and the work process information of the robot;
The control device according to claim 1 , wherein the change unit changes the route information based on information about a location where the worker, corresponding to the work process information, is present more frequently than a threshold value and the route information. the acquisition unit acquires a frequency of presence of the worker corresponding to the surrounding information based on the statistical information and surrounding information of the worker;
The control device according to claim 1 , wherein the change unit changes the route information based on information about a location where the frequency of the worker's presence corresponding to the peripheral information is higher than a threshold value and the route information. the acquisition unit acquires a frequency of presence of the worker corresponding to the two pieces of information based on the statistical information and at least two pieces of information selected from worker information of the worker, work process information of the robot, and surrounding information of the worker;
The control device according to claim 1 , wherein the change unit changes the route information based on information about a location where the frequency of the presence of the worker corresponding to the two pieces of information is higher than a threshold value and the route information. a setting unit that sets a protection area within the monitoring area to detect intrusion of the worker based on the changed route information;
13. The control device according to claim 1, comprising: A control device according to any one of claims 1 to 13;
The robot;
a detection unit that detects the position of the worker;
A control system comprising: The computer
a control step for controlling the operation of the robot;
an acquisition step of acquiring a frequency of the worker being present at the position based on statistical information of the worker's position within the monitoring area;
a changing step of changing the path information based on information about a location where the frequency of the worker's presence is higher than a threshold value and path information including at least a start point and an end point of the robot's movement ;
Run
In the control step, the operation of the robot is controlled based on the changed path information .
There are a plurality of locations where the frequency of the presence of the worker is higher than a threshold value,
In the changing step, when a distance between a second location, which is one of a plurality of locations where the frequency of the presence of the worker is higher than a threshold, and the start point or the end point is shorter than a predetermined distance, the route information is not changed based on information about the second location.
Control method. A program for causing a computer to execute each step of claim 15.